[UPDATE 8/4/11: Gigwalk now allows iPhone 3GS users to complete Microsoft Photosynth gigs. It previously restricted thousands of gigs to the iPhone 4, which has a 5-megapixel camera. The 3GS has a 3-megapixel camera. At the time the following post first published, only iPhone 4 users could make money off the Microsoft gigs.]
There is more than $35,000 in cash to be earned in South Florida from the iPhone Gigwalk app -- but most of that is attainable only if you have an iPhone 4 and some time on your hands.
First, an explainer of Gigwalk: It pays you around $4 to $5 for doing tasks on behalf of companies. Sometimes it's like being a secret shopper for a retail chain (example: send us a photo of the lipstick display in the store). Other times it will have a user fill out a questionnaire about an experience. It's similar to the FieldAgent iPhone app, which also pays for small tasks and surveys.
Microsoft has put thousands of assignments on Gigwalk at $4.75 a pop for users to take photos of establishments. This public "workforce" will be taking detailed photos of restaurants and stores, using the Photosynth app, which will then be embedded throughout Bing Maps.
The app currently lists 7,434 tasks in total around South Florida (and more than 116,000 gigs nationwide). There are more than 50,000 users since it launched in May. If you poke around, you'll find a few assignments that are not from Microsoft, so you can still make a few bucks even if you have an older iPhone model.